THE MODERN TREATMENT OF PARATHYROID INSUFFICIENCY1

Abstract

N 1926–27, Windaus and his coworkers (Chemical Laboratory of the University of Gottingen) first produced products of high antirachitic potency through irradiation of ergosterol with ultraviolet rays (1). A short time thereafter, a thousandfold overdose of irradiated ergosterol, calculated on its antirachitic potency, was found to produce a toxic effect: loss of appetite and weight, hypercalcemia, deposition of calcium in the soft tissues (especially in the kidneys and blood-vessel walls), circulatory im-pairment, and gastrointestinal bleeding (2). The ergosterol derivatives prepared by various forms of irradiation were not absolutely identical. Dry preparations kept sealed in a glass tube under vacuum for a long period of time lost their antirachitic potency without losing their toxicity. The destruction of vitamin D in irradiated ergosterol by aging could also be accomplished by means of heating. Finally, if the double bonds in the irradiated ergosterol were eliminated by hydrogenation, the antirachitic potency was destroyed, while all of the toxic effect was retained (3). This proved that the toxic action of overdosage of irradiated ergosterol was not a hypervitaminosis. As the toxic principle in these preparations.